Well it's been 2 months and the dealership still doesn't have an owners manual for me yet. Yesterday a dash light lit up unexpectedly, it was a green trailer, it stayed lit for about 2 minutes then went out. Can anyone tell me what it was trying to tell me

Normally that light comes on when a trailer is hooked up to the truck.
Can't say why it came on.
Mike

Do you have the trailer electrical hook up on the back of your truck, I wonder if this could be a sign of the box shorting out or having an error. Or do you have a lighted hitch cover?

Neither of those, just the rubber cover.

Do you know where the trailer electric hook-up plug is behind the tail light, if you know what it is that i am talking about see if something is plugged in there, if you don't know what i am talking about then i can post a picture of where it is on my 97 Range Rover, but i'm not sure if it's the exact same. It is possible that it is just an electrical fluke, just the other day I opened the door of the Range and the warning beep went off and the Service Engine light came on, and i had half a tank of fuel yet the fuel light came on, it all went away when the door shut, so that's always a possibility

OK, figured it out (well the cause, not the fix yet) when the guy was wiring in the new front turn signal on the left side on the ARB bumper he must have done something wrong because when the left turn signal is on is when the light flashes. So, time to figure out what's shorting what and fix it

I know this thread is 12 years old, but for historical purposes and future reference, the guy that wired the lights of his front bumper probably didn't do anything wrong.

When the OP added the new ARB bumper and the lights were connected, the system started picking up the extra load in the circuit and is assuming that this extra indicator is a trailer connected to his LR. Nothing wrong with the system and it was working correctly.

The same thing happened to me when I installed and ARB Sahara winch bumper. I changed the bumper light bulbs to LEDs and that took care of the green trailer flashing light.

Yes, the amperage draw across the flasher fuse would change, with added fixtures, so the ECM would recognize this and assume a trailer was causing the additional load, tripping the light on the dash.

Same goes for the cruise control, but in reverse theory. When folks change brake light bulbs to lower draw LED, the amperage draw diminishes...so, the ECM sees the drop in amperage and assumes there is a problem with the brake switch circuit. And when the ECM sees an incorrect amount of resistance...it won't allow the cruise to be set, since the brake switch turns off the cruise control, when applied. Think Toyota...when thinking about a cruise control system that wouldn't turn off when it should.

Brian.

Hi Brian, is there a fix for this? I have an 08 3.6 L322 and fitted 2010 led tail lights with resistors and a motherboard. They work fine but this year I fitted a new oem westfalia trailer module and harness. It works fine but occasionally the trailer light on the dashboard intermittently lights up when the trailer isn’t connected. I’m guessing because it is sensing an increased load somewhere?

Thanks in advance.

this section is for Discovery IIs so I think you would have a better chance figuring out your issue here